Resin article having plating layer and method of manufacturing the same

ABSTRACT

There is provided with a method of manufacturing a resin article having a plating layer. A portion of a surface of a resin article is selectively irradiated with ultraviolet rays. The resin article irradiated with ultraviolet rays is treated using an alkaline solution. An electroless plating catalyst is applied to the surface of the resin article treated using the alkaline solution. A plating layer is selectively deposited on a portion of the surface of the resin article that is not irradiated with ultraviolet rays by submerging the resin article applied with the electroless plating catalyst in an electroless plating solution.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a resin article having a plating layer and a method of manufacturing the same.

2. Description of the Related Art

A resin article on which a plating layer having a predetermined pattern is provided is useful as a circuit board, a conductive film, and the like. A method in which electroless plating is used has been known as a method of manufacturing such a resin article having a plating layer.

For example, Japanese Patent Laid-Open No. 2008-094923 discloses a method of manufacturing a circuit board using surface modification by means of ultraviolet rays. Specifically, first, the entire surface of a cycloolefin polymer material is irradiated with ultraviolet rays emitted from an ultraviolet lamp, and thus the surface of the cycloolefin polymer material is modified. An electroless plating layer is likely to be deposited on the modified region. Thereafter, a plating layer is formed on the entire surface of the modified cycloolefin polymer material by performing the electroless plating. Finally, photolithography and etching are performed so that the plating layer has a desired pattern.

Japanese Patent Laid-Open No. 2009-007613 discloses a method of forming the pattern of a plating thin layer on the surface of a polyimide resin substrate. Specifically, a resist pattern is formed on the surface of the polyimide resin substrate, and alkali modification, metal minute particle addition, and electroless plating are performed on a region exposed from an opening region of the resist pattern, as a result of which the plating thin layer is formed on the opening region of the resist pattern.

SUMMARY OF THE INVENTION

According to an embodiment of the present invention, a method of manufacturing a resin article having a plating layer comprises: selectively irradiating a portion of a surface of a resin article with ultraviolet rays; treating the resin article irradiated with ultraviolet rays using an alkaline solution; applying an electroless plating catalyst to the surface of the resin article treated using the alkaline solution; and selectively depositing a plating layer on a portion of the surface of the resin article that is not irradiated with ultraviolet rays by submerging the resin article applied with the electroless plating catalyst in an electroless plating solution.

According to another embodiment of the present invention, a resin article having a plating layer, manufactured by a method comprises: selectively irradiating a portion of a surface of a resin article with ultraviolet rays; treating the resin article irradiated with ultraviolet rays using an alkaline solution; applying an electroless plating catalyst to the surface of the resin article treated using the alkaline solution; and selectively depositing a plating layer on a portion of the surface of the resin article that is not irradiated with ultraviolet rays by submerging the resin article applied with the electroless plating catalyst in an electroless plating solution.

Further features of the present invention will become apparent from the following description of exemplary embodiments with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A and 1B are diagrams illustrating a method of manufacturing a resin article having a plating layer according to an embodiment.

FIG. 2 is a flowchart of a method of manufacturing a resin article having a plating layer according to an embodiment.

DESCRIPTION OF THE EMBODIMENTS

In order to form a plating layer having a desired pattern using the method described in Japanese Patent Laid-Open No. 2008-094923, photolithography and etching are required. It is also necessary that a resist pattern is formed through photolithography in the method described in Japanese Patent Laid-Open No. 2009-007613. Thus, there is a problem in that the methods described in Japanese Patent Laid-Open No. 2008-094923 and Japanese Patent Laid-Open No. 2009-007613 are costly and environmental load is high since a large amount of waste liquid is produced.

According to an embodiment of the present invention, a plating layer having a desired pattern can be formed on a resin article at low cost.

The inventor has known a technique for selectively modifying a portion of the surface of a resin article by applying the technique described in Japanese Patent Laid-Open No. 2008-094923 and irradiating only a portion of the resin article on which a plating layer is to be formed with ultraviolet rays emitted from an ultraviolet lamp. According to this technique, the plating layer is selectively deposited on the portion irradiated with the ultraviolet rays through electroless plating. Therefore, it is possible to form a plating layer having a desired pattern at low cost without performing photolithography and etching. However, the inventor found that in the case of using such a technique, an unnecessary plating layer was sometimes deposited also on a portion that was not irradiated with ultraviolet rays, depending on conditions, such as the type of resin article to be used.

As a result of studies, the inventor found that if the alkali treatment was performed on the resin article irradiated with ultraviolet rays, and then an electroless plating catalyst was applied to and electroless plating was performed on the resin article, surprisingly, the plating layer was selectively deposited on a portion that was not irradiated with ultraviolet rays. On the other hand, the plating layer was not deposited on the portion irradiated with ultraviolet rays. In this manner, the plating layer having a desired pattern could be formed at low cost without performing the photolithography step, the etching step, and the like.

Hereinafter, an embodiment to which the present invention can be applied will be described with reference to drawings. However, the scope of the present invention is not limited to the following embodiment. A method of manufacturing a resin article having a plating layer 100 according to an embodiment of the present invention includes an irradiation step, a treatment step, an applying step, and a plating step. Hereinafter, these steps will be described with reference to FIGS. 1A, 1B, and 2.

Irradiation Step

In the irradiation step (step S210), a portion 120 of the surface of a resin article 110 is selectively irradiated with ultraviolet rays. FIG. 1A shows the surface of the resin article 110, the ultraviolet rays-irradiation portion 120, and an ultraviolet rays non-irradiation portion 140. Irradiation with ultraviolet rays modifies the ultraviolet rays-irradiation portion 120.

In an embodiment, the resin article 110 is irradiated with ultraviolet rays in an atmosphere including oxygen or ozone. Specifically, the resin article 110 may be irradiated with ultraviolet rays in the air, for example. In another embodiment, in order to further promote modification, irradiation is performed in an atmosphere including ozone.

For example, if ultraviolet rays are emitted in an atmosphere including oxygen, the oxygen in the atmosphere is decomposed into ozone. Furthermore, reactive oxygen is produced in the process in which ozone undergoes decomposition. Also, bonds in molecules that constitute a resin are also cleaved at the surface of the resin. At this time, molecules constituting the resin react with the reactive oxygen, and the surface of the resin is oxidized, that is, a C—O bond, a C═O bond, a C(═O)—O bond (skeletal portion of a carboxyl group), and the like are formed on the surface of the resin. Also, a surface having minute roughness is formed in the ultraviolet rays-irradiation portion 120 along with such oxidation.

Energy of a photon having a specific wavelength will be expressed by the following equation.

E=Nhc/λ (KJ·mol⁻¹)

N=6.022×10²³ mol⁻¹ (Avogadro's number)

h=6.626×10⁻³⁷ KJ·s (Planck constant)

c=2.988×10⁸ m·s⁻¹ (light velocity)

λ=wavelength of light (nm)

Here, binding energy of an oxygen molecule is 490.4 KJ·mol⁻¹. Conversion of the binding energy of oxygen molecule into wavelength of light using the equation of photon energy gives approximately 243 nm. This indicates that the oxygen molecule in the atmosphere absorbs ultraviolet rays having a wavelength of 243 nm or less and is decomposed. Accordingly, ozone O₃ is produced. Furthermore, reactive oxygen is produced in the process in which ozone undergoes decomposition. At this time, if there are ultraviolet rays having a wavelength of 310 nm or less, ozone is efficiently decomposed to produce reactive oxygen. Furthermore, ultraviolet rays having a wavelength of 254 nm most efficiently decomposes ozone.

O₂ +hν(243 nm or less)→O(3P)+O(3P)

O₂+O(3P)→O₃(ozone)

O₃ +hν(310 nm or less)→O₂+O(1D)(reactive oxygen)

O(3P): oxygen atom in ground state

O(1D): excited oxygen atom (reactive oxygen)

There is no particular limitation on the method for irradiation with ultraviolet rays, and an ultraviolet lamp, an ultraviolet LED, or an ultraviolet laser can be used, for example. In an embodiment, ultraviolet rays are emitted from the ultraviolet lamp, or the like through a quartz/chromium mask, a metal mask, or the like on which a desired pattern is formed toward the resin article 110. Also, in another embodiment, the ultraviolet rays-irradiation portion 120 is scanned using ultraviolet rays emitted from the ultraviolet laser or the like.

There is no particular limitation on the wavelength of ultraviolet rays, and ultraviolet rays that promote modification of the surface of the resin article 110 are selected. In an embodiment, the wavelength of the ultraviolet rays is 243 nm or less. The ultraviolet rays having a wavelength of 243 nm or less further promote modification of the surface of the resin article 110. The ultraviolet rays having a wavelength of 243 nm or less can modify the surface of the resin article 110 in accordance with a minute pattern.

There is no particular limitation on the irradiation amount of ultraviolet rays, and the irradiation amount of ultraviolet rays can be appropriately selected so that plating is selectively deposited on the ultraviolet rays non-irradiation portion 140. In an embodiment, the cumulative irradiation amount of ultraviolet rays with regard to a dominant wavelength is 400 mJ/cm² or more, and in another embodiment, is 600 mJ/cm² or more. Also, in an embodiment, the cumulative irradiation amount thereof with regard to a dominant wavelength is 2000 mJ/cm² or less. In this specification, the irradiation amount and irradiation intensity of ultraviolet rays indicate the values at the dominant wavelength, unless otherwise stated. In this specification, the dominant wavelength refers to a wavelength having the highest intensity in a region of 243 nm or less. Specifically, in the case of a low pressure mercury vapor lamp, the dominant wavelength is 185 nm.

Of course, a plating deposition condition can change in accordance with the type of plating solution, type of resin article 110, contamination degree of the surface of the resin article 110, concentration, temperature, pH, and chronological deterioration of the plating solution, change in output from the ultraviolet lamp or the like, for example. In this case, it is sufficient that the irradiation amount of ultraviolet rays is appropriately determined with reference to the above-described numerical values.

In the present embodiment, the surface of the resin article 110 includes the ultraviolet rays-irradiation portion 120 and the ultraviolet rays non-irradiation portion 140. However, in an embodiment, the surface of the resin article 110 includes a portion that is to be irradiated with ultraviolet rays in a fixed amount or more, and a portion that is to be irradiated with ultraviolet rays in less than the fixed amount or is not to be irradiated with ultraviolet rays. In this embodiment, the portion that is to be irradiated with ultraviolet rays in the fixed amount or more corresponds to the portion selectively irradiated with ultraviolet rays, and the portion that is to be irradiated with ultraviolet rays in less than the fixed amount or is not to be irradiated with ultraviolet rays corresponds to the portion that is not selectively irradiated with ultraviolet rays. The portion that is to be irradiated with ultraviolet rays in the fixed amount or more is irradiated with more ultraviolet rays such that the plating layer 130 is not deposited in the plating step (step S240), which will be described later. On the other hand, the portion that is to be irradiated with ultraviolet rays in less than the fixed amount is irradiated with less ultraviolet rays such that the plating layer 130 is deposited in the plating step (step S240), which will be described later. Irradiation with ultraviolet rays toward the portion where the plating layer 130 is to be deposited as well is advantageous in that minute unevenness is formed on the surface of the resin article 110 and an adhesive force between the resin article 110 and the plating layer 130 is increased.

There is no particular limitation on the resin article 110 as long as the resin article 110 has a surface having a resin material that can be selectively modified by a combination of the irradiation step (step S210) and the treatment step (step S220). In an embodiment, the resin article 110 has a resin material having a low alkali-resistance. The resin material having a low alkali-resistance indicates a resin material whose surface is modified by the alkali treatment, or in other words, a resin material in which bonds between atoms are cleaved by the alkali treatment at the surface. Examples of resin materials that are likely to be modified by the alkali treatment include a polyimide resin, a polyamide resin, a polycarbonate resin, an acryl resin, and a polyester resin. In an embodiment, a resin material that produces a carboxyl group in hydrolysis, such as an ester bond, an amide bond, and an imide bond is used. For example, in the case where the polyimide resin is used as the resin material, if the alkali treatment is performed on the resin article 110, an imide ring is opened, as a result of which a carboxyl group or a carboxyl ion may be generated on the surface of the resin article 110.

The manufacturing method according to the present embodiment can be used for the resin article 110 having a polyimide resin or a polyamide resin on the surface thereof. Among the resins, the polyimide resin has excellent heat resistance and strength, and thus soldering (including reflowing) can be performed on a circuit board obtained by forming a plating layer pattern on the polyimide resin substrate.

There is no particular limitation on the shape of the resin article 110, and the resin article 110 may be a substrate, or a film, for example. Also, the resin article 110 may be configured by a plurality of resin materials, have a layered structure of a plurality of resin materials, or be a composite material having a covered structure obtained by covering the surface of another material with a resin material.

Treatment Step

In the treatment step (step S220), the resin article 110 irradiated with ultraviolet rays is treated with an alkaline solution. There is no particular limitation on the treatment method, and examples thereof include a method for submerging the resin article 110 in an alkali treatment solution, and a method for applying the alkali treatment solution onto the resin article 110.

In an embodiment, the alkali treatment is performed through submerging the resin article 110 in the alkali treatment solution. An aqueous solution of an alkali metal hydroxide, an alkaline earth metal hydroxide, or the like can be used as the alkali treatment solution. Specific examples of the alkali treatment solutions include an aqueous solution of sodium hydroxide and an aqueous solution of potassium hydroxide. After the alkali treatment, the resin article 110 may be washed using water or the like.

As a result of the alkali treatment, the ultraviolet rays-irradiation portion 120 of the resin article 110 is modified such that the plating layer is not deposited in the plating step (step S240). The reasons are not clear, but it is conceivable that one of the reasons is that the ultraviolet rays-irradiation portion 120 is changed by the alkali treatment. For example, the ultraviolet rays-irradiation portion 120 has a fragile surface due to irradiation with ultraviolet rays, and thus there is a possibility that the portion modified by the alkali treatment falls off. Thus, it is conceivable that a catalytic ion is unlikely to attach to the ultraviolet rays-irradiation portion 120 in the applying step (step S230), which will be described later. It is conceivable that this is the reason why the plating layer is not deposited on the ultraviolet rays-irradiation portion 120.

Also, the ultraviolet rays non-irradiation portion 140 of the resin article 110 is modified such that the plating layer is deposited in the plating step (step S240). It is conceivable that this is because the alkali treatment forms a hydrophilic group in the ultraviolet rays non-irradiation portion 140, and thus a catalytic ion is likely to attach to the ultraviolet rays non-irradiation portion 140 in the applying step (step S230), which will be described later.

The strength of the alkali treatment performed on the resin article 110 can be appropriately selected such that the plating layer is not deposited on the ultraviolet rays-irradiation portion 120 and the plating layer is deposited on the ultraviolet rays non-irradiation portion 140. In general, the stronger the alkali treatment is, or in other words, the higher the concentration of the alkali treatment solution is and the longer a submersion time period is, the plating layer is unlikely to be deposited on the ultraviolet rays-irradiation portion 120. Also, the stronger the alkali treatment is, the plating layer is also unlikely to be deposited on the ultraviolet rays non-irradiation portion 140. Of course, in order not to deposit the plating layer, the ultraviolet rays non-irradiation portion 140 needs a stronger alkali treatment than the ultraviolet rays-irradiation portion 120 does.

For example, in the case where the alkali treatment is performed on polyimide, a carboxyl group or a carboxyl ion is generated due to hydrolysis, whereas if an imide ring is completely hydrolyzed, a polymer chain is cleaved at that portion, and the molecule falls off, or in other words, the molecule dissolves in an alkaline solution. In other words, it is conceivable that in the alkali treatment, both the generation of carboxyl group or the carboxyl ion and the disappearance of the carboxyl group or the carboxyl ion due to falling off proceed. It is conceivable that if the alkali treatment is strong, the falling off speed increases in particular.

In an embodiment, the submersion time period for the resin article 110 into the alkali treatment solution is 1 second or more, in another embodiment, 5 seconds or more, and in a further embodiment, preferably 20 seconds or more. Also, in an embodiment, the submersion time period is 300 seconds or less, in another embodiment, 100 seconds or less, and in a further embodiment, 60 seconds or less.

Also, in an embodiment, the concentration of the alkali metal hydroxide included in the alkali treatment solution is 0.010 mol/L or more, in another embodiment, 0.10 mol/L or more, and in a further embodiment, 0.30 mol/L or more. Also, in an embodiment, the concentration of the alkali metal hydroxide included in the alkali treatment solution is 10 mol/L or less, and in another embodiment, 3.0 mol/L or less. Moreover, in another embodiment, the pH of the alkali treatment solution is 12.0 or more, in another embodiment, 13.0 or more, and in a further embodiment, 13.5 or more.

Applying Step

In the applying step (step S230), the electroless plating catalyst is applied to the surface of the resin article 110 that was treated with the alkaline solution. The electroless plating catalyst can be applied in accordance with a conventionally known method.

For example, the electroless plating catalyst can be applied by using two steps, which will be described below.

(Step 1) The resin article 110 is submerged in a solution containing catalytic ions. In an embodiment, an electroless plating catalytic ion having a positive charge is used as the catalytic ion. It is conceivable that if the carboxyl group or the like is formed on the surface of the resin article 110 by the alkali treatment, for example, the electroless plating catalytic ion having a positive charge is likely to be absorbed by the surface of the resin article 110. As described above, when the resin article 110 is submerged in a solution containing catalytic ions, the catalytic ion is unlikely to attach to the ultraviolet rays-irradiation portion 120 of the resin article 110, whereas the catalytic ion is likely to attach to the ultraviolet rays non-irradiation portion 140.

(Step 2) Catalytic ions are reduced by submerging the resin article in a solution containing a reducing agent. In this manner, the catalyst is deposited. It is conceivable that the catalytic ion is likely to attach to the ultraviolet rays non-irradiation portion 140 of the resin article 110, and thus as a result of reduction, a larger amount of catalysts is applied to the ultraviolet rays non-irradiation portion 140 compared to the ultraviolet rays-irradiation portion 120. A conventional reducing agent can be adopted as the reducing agent, and as described in International Publication No. 2007/066460, for example, hydrogen gas, dimethylamine borane, sodium borohydride, or the like can be used.

Examples of the electroless plating catalytic ion having a positive charge include a metal complex having an amine-based ligand, in particular, a metal complex having a basic amino acid as the ligand can be used. One example thereof is a basic amino acid complex of palladium. The basic amino acid complex of palladium is a complex of a palladium ion and a basic amino acid. There is no limitation on the palladium ion, and a divalent palladium ion is often used. The basic amino acid may be a natural amino acid or an artificial amino acid. In an embodiment, the amino acid is an α-amino acid. Examples of the basic amino acid include an amino acid having a basic substituent such as an amino group or a guanidyl group on a side chain. Examples of the basic amino acid include lysine, arginine, and ornithine.

Examples of the basic amino acid complex of palladium include the ones described in International Publication No. 2007/066460. Specific examples of the basic amino acid complex of palladium include the one expressed by Formula (I) below.

In Formula (I) above, L₁ and L₂ independently express an alkylene group having one to ten carbons, and R₃ and R₄ independently express an amino group or a guanidyl group. Examples of the alkylene group having one to ten carbons include a linear alkylene group such as a methylene group, a 1,2-ethanediyl group, a 1,3-propanediyl group, and an n-butane-1,4-diyl group. Although two amino groups are coordinated in the trans position in Formula (I) above, two amino groups may be coordinated in the cis position. Also, the basic amino acid complex of palladium may be a mixture of a cis product and a trans product. Also, instead of palladium, another metal atom that functions as the electroless plating catalyst may be used.

Plating Step

In the plating step (step S240), the resin article 110 applied with the electroless plating catalyst is submerged in the electroless plating solution. As a result of this, as shown in FIG. 1B, the plating layer 130 is deposited on the ultraviolet rays non-irradiation portion 140 of the surface of the resin article 110. As described above, it is conceivable that a larger amount of catalysts are applied to the ultraviolet rays non-irradiation portion 140 than the ultraviolet rays-irradiation portion 120. It is conceivable that the plating layer 130 is thus selectively deposited on the ultraviolet rays non-irradiation portion 140. Also, as described above, the plating layer 130 cannot be deposited on the ultraviolet rays-irradiation portion 120 by appropriately performing the irradiation step (step S210), the treatment step (step S220), and the applying step (step S230).

There is no particular limitation on a specific method for electroless plating. Examples of electroless plating that can be adopted include electroless plating in which a formalin-based electroless plating bath is used and electroless plating in which formalin is not required and hypophosphorous acid that is deposited at a low rate is used as the reducing agent. Also, in order to form a thicker plating layer, the plating layer 130 may be formed using a high-speed electroless plating method. Specific examples of electroless plating further include electroless nickel plating, electroless copper plating, and electroless copper/nickel plating.

The electroless plating conforming to such a method can be performed using an electroless plating solution set such as a Cu—Ni plating solution set “AISL” available from JCU Corporation, for example.

Since the plating layer formed by electroless plating in this manner is often thin, the thickness of the plating layer may be increased by further performing electroplating. There is no limitation on the material for a metal layer provided by electroplating, and examples thereof include copper, nickel, a copper-nickel alloy, zinc oxide, zinc, silver, cadmium, iron, cobalt, chromium, a nickel-chromium alloy, tin, a tin-lead alloy, a tin-silver alloy, a tin-bismuth alloy, a tin-copper alloy, gold, platinum, rhodium, palladium, and a palladium-nickel alloy. Also, silver or the like may be deposited on the plating layer 130 through displacement plating.

According to the present embodiment, portions of the resin article 110 in which the plating layer is not to be formed are selectively irradiated with ultraviolet rays, and thus it is possible to obtain a resin article having a plating layer 100 in which the plating layer is selectively formed. According to the present embodiment, the plating layer having a desired pattern can be formed without performing photolithography and etching, and thus it is possible to reduce the number of steps required to produce the resin article having a plating layer 100, or in other words, it is possible to reduce cost.

EXAMPLE Example 1-1

A polyimide sheet (Kapton EN200 available from DU PONT-TORAY CO., LTD., thickness: 50 μm) was used as the resin article 110.

First, the portion 120 of the resin article 110 on which a plating layer is not to be formed was irradiated with ultraviolet rays via a photomask in the air. The condition of irradiation with ultraviolet rays was as follows.

Low pressure mercury vapor lamp: UV-300 available from SAMCO INC. (dominant wavelength: 185 nm, 254 nm)

Irradiation distance: 3.5 cm

Luminous intensity at irradiation distance of 3.5 cm: 5.40 mW/cm² (254 nm)

-   -   1.35 mW/cm² (185 nm)

Irradiation time: 10 minutes

Next, the alkali treatment was performed on the resin article 110 irradiated with ultraviolet rays. Specifically, an alkali treatment solution (pH 13.58: actual value) used in the Cu—Ni plating solution set “AISL” available from JCU Corporation was used, the solution was heated to 50° C., and the resin article 110 was submerged therein for 5 seconds. Thereafter, the resin article 110 was stirred and washed in pure water at 50° C. for 1 minute.

Next, a catalytic ion applying treatment was performed on the resin article 110 that was subjected to the alkali treatment. Specifically, an activator solution containing a palladium (II) basic amino acid complex (product name “ELFSEED ES-300” available from JCU Corporation) was used, and the resin article 110 was submerged therein at 50° C. for 2 minutes. Thereafter, the resin article 110 was washed in pure water at 25° C. by moving the resin article 110 back and forth three times.

Next, a reduction treatment was performed on the resin article 110 that was subjected to alkaline washing. Specifically, an accelerator solution (product name “ELFSEED ES-400” available from JCU Corporation) was used, and the resin article 110 was submerged therein at 35° C. for 2 minutes. Thereafter, the resin article 110 was washed in pure water at 25° C. by moving the resin article 110 back and forth three times, and the resin article 110 was then dried using a drier.

Next, the electroless copper/nickel plating was performed on the resin article 110 that was subjected to the reduction treatment. Specifically, the electroless Cu—Ni plating solution used in the Cu—Ni plating solution set “AISL” available from JCU Corporation was used, the solution was heated to 60° C., and the resin article 110 was submerged therein for 5 minutes. Thereafter, the resin article 110 was washed in pure water at 25° C. by moving the resin article 110 back and forth three times. In this manner, the resin article having a plating layer 100 was produced.

In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120, whereas the plating layer was deposited on the ultraviolet rays non-irradiation portion 140.

Example 1-2

Similarly to Example 1-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 10 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120, whereas the plating layer was deposited on the ultraviolet rays non-irradiation portion 140.

Example 1-3

Similarly to Example 1-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 20 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays irradiation portion 120, whereas the plating layer was deposited on the ultraviolet rays non-irradiation portion 140.

Example 1-4

Similarly to Example 1-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 60 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120. Although the plating layer was deposited on most of the ultraviolet rays non-irradiation portion 140, the plating layer was not deposited on a portion thereof.

Example 1-5

Similarly to Example 1-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 120 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120. Although the plating layer was deposited on most of the ultraviolet rays non-irradiation portion 140, the plating layer was not deposited on a portion thereof. The portion where the plating layer was not deposited was larger than that in Example 1-4.

Example 1-6

Similarly to Example 1-1, the resin article having the plating layer 100 was produced, except that the alkali treatment was not performed. In the obtained resin article having the plating layer 100, although the plating layer was deposited on some parts of the ultraviolet rays-irradiation portion 120, almost all of the surface of the resin article 110 was exposed.

Example 2-1

Similarly to Example 1-1, the resin article having the plating layer 100 was produced, except the following points. Specifically, an activator solution having a threefold concentration compared to Example 1-1 was used in the catalytic ion applying treatment. Also, in the catalytic ion applying treatment, the resin article 110 was submerged in the activator solution for 5 minutes. Also, in the reduction treatment, the resin article 110 was submerged in the accelerator solution for 4 minutes. In this manner, the experiment was conducted under a condition in which the electroless plating catalyst is more likely to be applied onto the resin article 110 than that in Example 1-1.

In the obtained resin article having the plating layer 100, the plating layer was deposited on most of the ultraviolet rays-irradiation portion 120. Moreover, the plating layer was also deposited on the ultraviolet rays non-irradiation portion 140.

Example 2-2

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 10 seconds. In the obtained resin article having the plating layer 100, the plating layer was deposited on most of the ultraviolet rays-irradiation portion 120. Moreover, the plating layer was deposited on the ultraviolet rays non-irradiation portion 140.

Example 2-3

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 20 seconds. In the obtained resin article having the plating layer 100, the plating layer was hardly deposited on the ultraviolet rays-irradiation portion 120, whereas the plating layer was deposited on the ultraviolet rays non-irradiation portion 140.

Example 2-4

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 60 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120, whereas the plating layer was deposited on the ultraviolet rays non-irradiation portion 140.

Example 2-5

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 120 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120. Although the plating layer was deposited on most of the ultraviolet rays non-irradiation portion 140, the plating layer was not deposited on a portion thereof.

Example 2-6

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 180 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120. On the other hand, although the plating layer was deposited on most of the ultraviolet rays non-irradiation portion 140, the plating layer was not deposited on a portion thereof. The portion where the plating layer was not deposited was larger than that in Example 2-5.

Example 2-7

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that in the alkali treatment, the resin article 110 was submerged in the alkali treatment solution for 240 seconds. In the obtained resin article having the plating layer 100, the plating layer was not deposited on the ultraviolet rays-irradiation portion 120. On the other hand, with regard to the ultraviolet rays non-irradiation portion 140, there are a portion where the plating layer was deposited and a portion where the plating layer was not deposited. The portion where the plating layer was not deposited was larger than that in Example 2-6.

Example 2-8

Similarly to Example 2-1, the resin article having the plating layer 100 was produced, except that the alkali treatment was not performed. In the obtained resin article having the plating layer 100, although the plating layer was deposited on some parts of the ultraviolet rays-irradiation portion 120, almost all of the surface of the resin article 110 was exposed.

It was found that as described above, by performing the alkali treatment after irradiation with ultraviolet rays, the electroless plating could be performed such that the plating layer was deposited on the ultraviolet rays non-irradiation portion 140. Meanwhile, it was found that by performing the alkali treatment under an appropriate condition, the electroless plating could be performed such that the plating layer was not deposited on the ultraviolet rays-irradiation portion 120.

Also, it was found that if a time period for the alkali treatment is short, the plating layer is likely to be deposited on the ultraviolet rays-irradiation portion 120, whereas if the time period for the alkali treatment is long, the plating layer is unlikely to be deposited on the ultraviolet rays non-irradiation portion 140. Furthermore, it was found that the tendency for the plating layer to be deposited also depends on conditions for the catalytic ion applying treatment, the reduction treatment, and the like. However, it is conceivable that the plating layer can be selectively deposited on the ultraviolet rays non-irradiation portion 140 under an arbitrary condition by appropriately adjusting the strength of the alkali treatment (a treatment time period, the concentration of the alkaline solution, for example) with reference to the above-described results.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

This application claims the benefit of Japanese Patent Application No. 2014-135121, filed Jun. 30, 2014, which is hereby incorporated by reference herein in its entirety. 

What is claimed is:
 1. A method of manufacturing a resin article having a plating layer, comprising: selectively irradiating a portion of a surface of a resin article with ultraviolet rays; treating the resin article irradiated with ultraviolet rays using an alkaline solution; applying an electroless plating catalyst to the surface of the resin article treated using the alkaline solution; and selectively depositing a plating layer on a portion of the surface of the resin article that is not irradiated with ultraviolet rays by submerging the resin article applied with the electroless plating catalyst in an electroless plating solution.
 2. The method according to claim 1, wherein the applying comprises treating the resin article using a solution of an electroless plating catalytic ion having a positive charge.
 3. The method according to claim 1, wherein a pH of the alkaline solution is 12.0 or more.
 4. The method according to claim 1, wherein the alkaline solution is a solution of an alkali metal hydroxide.
 5. The method according to claim 1, wherein the treating comprises submerging the resin article in the alkaline solution for not less than 1 second and not more than 100 seconds.
 6. The method according to claim 1, wherein the surface of the resin article includes a polyimide resin or a polyamide resin.
 7. The method according to claim 1, wherein in the depositing, the plating layer is not deposited on the portion irradiated with ultraviolet rays.
 8. A resin article having a plating layer, manufactured by a method comprising: selectively irradiating a portion of a surface of a resin article with ultraviolet rays; treating the resin article irradiated with ultraviolet rays using an alkaline solution; applying an electroless plating catalyst to the surface of the resin article treated using the alkaline solution; and selectively depositing a plating layer on a portion of the surface of the resin article that is not irradiated with ultraviolet rays by submerging the resin article applied with the electroless plating catalyst in an electroless plating solution. 